The present invention relates to split roller bearings and more particularly to cages and cage components therefor.
As is known, a split roller bearing of conventional design employs inner and outer rings between which a series of rollers are held in spaced apart relationship by a cage to locate in raceways formed by the rings. The bearing is made to separate into two halves about a diametric plane and each half of the bearing is then composed of semi-circular inner and outer ring components and a semi-circular cage component. It is necessary for the individual cage components to retain the associated rollers when the bearing is separated. Conventional cage components are made from die-cast aluminium or from machined aluminium or gun metal. To fasten the cage components together to form a continuous ring it is conventional to employ separate fastening clips or spring plates.
A general object of the invention is to provide an improved form of cage component for use in split roller bearings.
CH-A-365582 which has an English language equivalent GB-A-919983 describes a circular cage for a roller bearing which is formed from a blank which is bent to form a continuous wall and bars excluding therefrom and spaced apart to define pockets for receiving the rollers.
In one aspect, and as is known from GB-A-919983, the invention provides a cage component for use in a roller bearing; said component being made from a pair of separate parts or blanks bent to shape and joined together, the blanks having continuous wall portions for overlapping the ends of rollers as the sides of the component and projections spaced apart along the continuous wall portions and aligned to form pockets for receiving and locating the rollers with at least some of the corresponding aligned projections of the blanks being joined to one another at a central region between the continuous wall portions. In contrast to GB-A-919983, and in accordance with the invention, the blanks are semi-circular and the component is equipped with integral inter-engageable complementary releasable fixing means at its opposite ends for enabling the component to be detachably interconnected with another similar component to form a complete circular cage and the regions where the aligned projections of the blanks are joined together are defined by face-to-face overlapping portions of the projections extending predominantly perpendicular to the continuous wall portions.
Conveniently, the separate parts of the cage component are made from blanks or sections pressed or otherwise cut from mild steel sheet and then bent to shape.
In one design the continuous wall portion of each blank has sets of spaced-apart projections along both its side edges and these projections are bent to extend perpendicular to the wall portion and parallel to one another to define the reception pockets for the rollers. Some of the edges of the projections which define the pockets are located do use radially inwardly of the common pitch circle diameter exending through the centres of the rollers.
In another design, the continuous wall portion has spaced-apart projections along just one of its side edges Inner regions of the projections adjacent the wall portion are bent perpendicular to the wall portion and outer regions are bent at an angle, e.g. 135xc2x0 in one direction and another opposite direction axially outwardly fromn the wall portion which forms the side of the cage component. Outermost regions of the projections remote from the side wall portion then extend parallel to the innernost regions but in a different axial plane. Between the projections there are inclined intermediate regions preferably formed with semi-circular side edges which match the curvature of the rollers. These side edges then define the pockets for the rollers which are at least partially located during use radially inwardly of the common pitch circle diameter extending through the centres of the rollers. The outermost regions of the projections of the separate parts overlap one another and are joined together as described previously to create the semi-circular cage component.
To assemble a complete cage, two cage components constructed as described can be fitted together. To enable this fixing each cage component may have one or more integral hook-like projections at one end. These hook-like projections can each engage in a recess or opening in the opposite end. In a preferred construction the hook like projections simply overlap with end regions of the continuous wall portion at the opposite end. Dimples and holes can locate the hook-like projections of the cage components to the opposite end so that the cage components can be snap-fitted together. Notches can be provided at the ends of the cage components to provide a location for a tool used to detach the cage components from one another.
In a further aspect, and as is known fom GB-A-919983, the invention provides a method of making a cage component for a roller bearing which comprises producing a pair of blanks or sections each with a continuous wall portion with projections spaced apart around the wall portion, bending the continuous wall portion relative to the projections so that at least some regions of the projections extend generally perpendicular to the wall portion, aligning the projections of the blanks to define roller-locating pockets and interconnecting the blanks after bending so that the wall portions are spaced apart by at least some of the projections which extend in the same general direction and are fixed together at a central region between the wall portions.
In contrast to GB-A-919983, and in accordance with the invention, the blanks are semi-circular and equipped with means for creating integral inter-engageable releasable fixing means at the opposite ends of the component to enable the component to be interconnected with another similar component to form a complete circular cage and the regions where the aligned projections are joined together are defined by face-to-face overlapping portions of the projections extending predominantly perpendicular to the wall portions.
The blanks and the subsequent formed sections can be provided with the complementary inter-engageable integral releasable fixing means such as:
a) hooks or lugs at one end
b) receiving means for the hooks or lugs such as recesses, openings or cut-outs at their opposite ends and/or
c) dimples and holes which snap-fit together.
A complete cage can then be assembled by inter-fitting the fixing means at the ends of the previously formed cage components.
The invention may be understood more readily, and various other aspects and features of the invention may become apparent, from consideration of the following description.